LA JOLLA, Calif. - The California Coastal Commission Thursday unanimously upheld the city of San Diego's ban on people going down to the beach at the Children's Pool in La Jolla during harbor seal pupping season.

The City Council passed the prohibition in March, but it hadn't taken effect, pending action by the commission, which is in the midst of four days of meetings at the Catamaran Resort in Pacific Beach.

The commission approved the ban for a five-year period, and will require annual monitoring and reports.

The City Council passed the law after a rope barrier failed to keep people from bothering the seals and their offspring. According to a staff report, a city ranger posted to the Children's Pool observed 30 occasions over a recent one-year period when seals were forced back into the water by humans -- half during pupping season.

Supporters of the prohibition said there were actually many more instances when that happened.

"Some people don't know how to behave around seals," former San Diego Councilwoman Donna Frye told the commissioners.

The new plan prohibits people from taking to the beach from Dec. 15 to May 15, the traditional breeding season for the seals. The rope barrier will be up the rest of the year.

"This is a compromise where the seals can have five months and then people and seals can have the rest of the year," said Adrian Kwiatkowsky with the Seal Conservancy.

The Children's Pool was deeded to the city in 1931 to be a safe swimming spot for youngsters. Seals moved into the area in the 1990s and have become the focus of a dispute between animal-rights supporters and beach-access advocates.

Commission staff reported that water quality is poor in the area because of the seals, so it is not a good place for swimming, anyway. Several nearby beaches with better water quality can be used by people, some within walking distance, the staff said.

One public speaker called the sand at the beach a "toxic waste dump" that a parent wouldn't want a child digging into.

Supervisor Greg Cox, the San Diego region's representative on the commission, said the county doesn't even both testing for water quality at the Children's Pool anymore.

"It's permanently signed with a sign that says 'warning, contact with this water may cause illness. Bacteria levels exceed health standards.' That's a permanent condition at the Children's Pool," Cox said.

The commissioners asked city officials to study the possibility of improving sand and water quality improvements before returning to the commission for renewal in five years. They were also asked to look into better access to the sand for the disabled.

The public will still be allowed access to the area's breakwater for walking, fishing or viewing the seals. The city plans to install a chain across the stairs to the beach, however.

Councilwoman Sherri Lightner, who represents the area, cast one of three dissenting City Council votes and opposed the ban before the commission.

"Seals and humans have long been able to peacefully coexist and share this beach," Lightner said. She called the issue "a people problem" with passionate representatives on both sides.

None of the La Jolla community groups support the closure, Lightner said. She said closing a public beach would be "an unusual precedent."

"When you close the beach entirely, that's no compromise," said Ken Hunrichs, who added that closing the beach even temporarily would open the door to other beach closures up and down the coast.

Councilman Ed Harris, who represents Mission and Pacific beaches, along with Point Loma, also spoke out in opposition.

A representative of Councilwoman Marti Emerald read her message of support. Former Supervisor Pam Slater-Price also spoke out to back the ordinance.

Opponents contend the seal population is exploding and that they are not a threatened or endangered species. Supporters of the closure, however, said harbor seals require a sandy beach during pupping season, and cannot make use of nearby rocks like sea lions can.

The approval by the commission came in a pair of unanimous votes -- one for a permit to close the beach during pupping season, and the other to amend La Jolla's coastal plan.

The commission will meet again on Friday, but no San Diego items are on the final-day agenda.

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